Answers

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  What are the common general-purpose grades of carbon steel pipes?

  Internationally, carbon steel plates primarily adhere to mainstream standard systems from the United States, Europe, and Japan. The American ASTM A36 is a common general-purpose structural steel with excellent weldability and formability, widely used in construction and bridges. High-quality carbon steels typically use the AISI/SAE series, such as AISI 1020 or 1045, for manufacturing mechanical components. Structural steels like S235 and S355 in the European standard system, where the numbers denote minimum yield strength, are commonly employed in various engineering projects. Japanese designations like SS400 (structural steel) and S45C (mechanical structural steel) are also widely circulated in Asia. Additionally, specialized grades exist for specific applications, such as pressure vessel steel ASTM A516 and cryogenic steel ASTM A537, meeting stringent requirements in energy, chemical, and other sectors.
  

  
  
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  I need to purchase a batch of hot-dip galvanized steel sheets SGCC, thickness 1.2-2.0mm for engineering project in the Middle East. can you provide FOB quote for 32-ton order, including the approximate delivery time? please note: MTC required

  We have the capacity to supply 32 tons of SGCC hot-dip galvanized steel sheets for your Middle East project, along with the required MTC certificate. Considering the close relationship between steel sheet specifications (such as thickness, width, and zinc coating) and price and delivery time, to ensure an accurate quote, you can first contact me quickly to confirm the final parameters.
  After understanding all the details, we will prepare a formal quotation and exact delivery time for you.
  WhatsApp/WeChat: +86 198 1937 3947
  lydia@yangtzesteel.com

  
  
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  The Difference Between Pre-galvanized Pipes and Hot-Dip Galvanized Pipes？

  Pre-galvanized pipes are manufactured by coating a layer of zinc onto the surface of cold-rolled or hot-rolled steel sheets, forming galvanized sheets, and then processing and welding them into pipes. The iron material is manufactured first, and then galvanized. Hot-dip galvanized pipes, on the other hand, are manufactured by immersing the iron pipe in molten zinc after it has been cooled to a certain temperature, allowing the iron and zinc to react and form a zinc layer. In other words, the galvanizing process for hot-dip galvanized pipes is performed after the pipe is manufactured.
  
  In terms of appearance, pre-galvanized pipes have a silver-gray appearance, a smooth surface, and good corrosion resistance. However, their corrosion resistance is relatively limited, making them suitable for applications requiring a smooth surface. They are corrosion-resistant, wear-resistant, and have high strength, but if used in a humid environment for extended periods, the zinc layer can easily corrode and peel off, significantly reducing their corrosion resistance.
  
  Hot-dip galvanized pipes have a silver-white appearance, a rough surface, and even better corrosion resistance. They have good corrosion resistance, a long service life, and can adapt to various harsh environments, thus having a wider range of applications. However, its drawback is that the surface is relatively rough, making it unsuitable for applications requiring high surface finish.